Instant Karma works - or - Your watch is not stronger than the train
This morning, some stocky fellow dressed like a leftover from the late 1970s was running a few seconds late for the train. As the train doors were closing, he jams himself into them and forces them open.
Now, the doors on this train are not like elevator doors. They will not re-open if they hit something while closing. They will keep closing and hold onto whatever's between them, regardless of if it's a purse, jacket or arm. If they we able to re-open, the trains would never be able to leave as people would be holding the doors open for their friend making their way down the escalator.
They're also notoriously intolerant of being forced open. It's not uncommon for a train to be damaged and taken out of service because some fool forced the doors open and broke the mechanism. Not a very good or robust design, but that's what it is.
What makes this morning's idiot special was that when he wedged himself into the closing doors and pried them open was that his watch got involved and was broken. Awww.... Maybe next time he'll remember that and not attempt to screw up several hundred innovent commuters' morning.